1. Field of the Invention
This invention relates to auxiliary traction devices for vehicles and more particularly, to a traction device which is positioned beneath a vehicle and is designed to provide traction under circumstances where the vehicle wheels lose traction due to excessively deep ruts. In a first preferred embodiment the traction device is characterized by a rotating endless belt mounted on a pair of drums located between the front and rear wheels and provided with spaced angle iron or angle plate members which rotate with the belt and contact the crown of terrain traversed by the vehicle to provide auxiliary traction. In another preferred embodiment the traction device includes a parallel endless chain system carried by sprockets provided on rotating shafts and including transversly-mounted angle iron or angle plate segments bolted in spaced relationship to the chains. As the chains rotate, the angle plate or angle iron segments contact the crown of the terrain to achieve the desired traction.
The traction device for vehicles is an accessory for all vehicles which are operated in off-road situations, as well as on well maintained roads during emergency conditions such as mud slides, snow and ice and other conditions which render traction of the drive wheels of the vehicle difficult due to a "high center" condition of the vehicle. The traction device is useful when the vehicle is incapable of forward or reverse movement by conventional wheel action under circumstances where the vehicle wheels are in deep ruts and the frame of the vehicle is resting on the crown of the terrain which is being traversed. In such a high center situation the traction device can be implemented to provide the necessary traction to remove the vehicle from a mired or stuck condition. Accordingly, this invention relates to a device for providing auxiliary traction for a vehicle in a mired condition wherein the driven wheels of the vehicle have lost their tractive ability in deeply rutted or soft spots in any terrain.
2. Description of the Prior Art
Many different techniques have been developed in the prior art for removing a vehicle from a mired or stuck condition. For example, the powered wheels of vehicles have been used in the prior art as a source of motive power for such purposes. It is known, for example, to mount a winch drum on one of the driven rear wheels of a vehicle and to anchor one end of a cable wound on a winch drum to a solid object spaced from the vehicle, in order to remove the vehicle from a mired or immobile condition. An early winch for mounting on one of more of the driven wheels of a vehicle is disclosed in a "Draft Appliance for Automobiles" in U.S. Pat. No. 1,054,831, patented on Mar. 4, 1913, to G. V. DePeel. The apparatus of this invention includes a spool mounted to the hub of a driven rear wheel and threaded through a tension or friction guide carried by the bumper to a stake, tree or other immobile object. The wheel is then rotated by racing the engine to wind the rope on the spool and remove the vehicle from its immobilized position.
Other techniques for removing vehicles from mired or stuck conditions include the use of tractor and traction devices, many of which are driven by the powered wheels of the vehicle. U.S. Pat. No. 1,296,309, dated Mar. 4, 1919, to R. J. Netzel, entitled "Tractor Device for Motor Vehicles" is an early design of such a vehicle. The Netzel device includes a pair of caterpillar tractors mounted in spaced relationship on sprockets and driven by the wheels of the vehicle to increase vehicle traction. A "Motor Car" is disclosed in U.S. Pat. No. 1,355,953, dated Oct. 19, 1920, to Leopole Salvator Habsburg-Lothringen. This patent also discloses a pair of caterpillar treads mounted as outriggers between the front and rear wheels of the motor car and driven by the front wheels by means of chains and sprockets, to aid vehicle traction. U.S. Pat. No. 1,443,963, dated Feb. 6, 1923, to A. Monsen, discloses a "Selt-Propelled Vehicle", which also discloses a pair of caterpillar treads driven by sprockets in association with a power take-off from the vehicle engine, the caterpillar treads being adjustable for disposition in selective engagement with the ground. An "Endless Track Attachment for Trucks" is disclosed in U.S. Pat. No. 1,729,374, dated Sept. 24, 1929, to C. S. Ehrhart. The "Endless Track Attachment for Trucks" includes an endless track which serves as a booster for aiding traction. The endless track can be raised from and lowered to engage the ground and is driven by means of a chain drive from the transmission mechanism or differential drive of the vehicle. U.S. Pat. No. 2,105,042, dated Jan. 11, 1938, to A. Kegresse, discloses a "Motor Vehicle with Variable Propulsion", which includes a pair of endless tracks in association with a driving axle which is mounted on the chassis of a vehicle between the front and rear wheel axles, and drive sprockets provided on each end of the driving axle to carry the endless track. The driven axle is powered by an electric motor operated by the driver. U.S. Pat. No. 2,714,933, dated Aug. 9, 1955, to F. D. Harris, discloses an "Auxilary Endless-Tread Traction Device for Vehicles", which includes a frame suspended from the underside of a vehicle adjacent one of the vehicle driven wheels, a hydraulic system operable to cause upward and downward adjustment of the frame, and toothed rollers mounted on the frame and having a cleated traction belt mounted thereon and disposed so as to bite into the supporting surface to provide added traction for the vehicle when the frame is adjusted downwardly. A drive linkage extends from the drive wheel of the vehicle to the rollers to drive the belt. A "Wheeled Vehicle with Rotatable Endless Track" is disclosed in U.S. Pat. No. 4,204,583, dated May 27, 1980, to Hirozumi Toyoura. The wheeled vehicle of this invention includes a rotatable endless track device disposed between the front and rear wheels, a system for selectively raising and lowering the endless track device with respect to the chassis and a connecting apparatus for linking the endless track with a source of driving power when the track is lowered and brought into contact with a road surface.
One of the problems with existing motor vehicles having traction-enhancing mechanisms built therein is the complexity and accompanying susceptiblity of such mechanisms to breakdown and the expense of maintenance. In the case of dual track mechanisms, the machine is particularly expensive to maintain and operate because the design generally necessitates a complicated, heavy mechanism due to transmission of power to two heavy propelling devices, and also on account of the more sophisticated suspension requirements of the vehicle. It is known, for example, that it is very difficult to provide an efficient vehicle for an integral endless track system. Furthermore, in the case of auxiliary traction devices which are driven from a common axle, these devices must rotate at the same speed as the driven wheel. However, since the diameter of the toothed sprocket which is usually used to drive the endless track is generally smaller than that of the carrying wheel, the very appreciable relative difference in speed developed results in poor operating efficiency.
Accordingly, it is an object of this invention to provide a traction device for vehicles which is simple in construction, easy to operate and is mounted in fixed deployment under circumstances where the vehicle is positioned in a "high center" driving circumstance and requires additional traction to move.
Another object of this invention is to provide a traction device for vehicles, which in a first preferred embodiment is characterized by a rotating belt provided with spaced angle iron, angle plate or channel-shaped traction members, with the belt rotated on a pair of drums to aid vehicle traction in deeply rutted terrain.
A still further object of this invention is to provide a traction device for vehicles which, in a second preferred embodiment is characterized by rotating chains provided in spaced relationship on sprockets carried by rotating axles, the chains further provided with transversly oriented channel-shaped members, angle plates or angle iron members for aiding vehicle traction when the crown of the terrain traversed contacts the chains and channel-shaped members or angle plates due to excessively deep ruts.
Still another object of this invention is to provide a traction device for vehicles which includes a simply constructed, inexpensive device for enhancing the traction of a vehicle, which device includes an endless belt, one or more chains, or a combination of such a belt and at least one chain, rotatably mounted beneath the vehicle and carrying multiple, spaced angle plates or channel-shaped members for contacting the crown of the terrain being traversed by the vehicle, under circumstances where the ruts are excessively deep, to provide auxiliary traction for the vehicle.
A still further object of this invention is to provide a new and improved traction device for vehicles, which includes rotatably mounted angle plates or channel-shaped members provided in spaced relationship beneath a vehicle and driven by a separate source of power from the vehicle engine or wheels, which traction device is designed to contact the terrain beneath the vehicle in a "high center" situation to aid vehicle traction.